Paint brush construction

ABSTRACT

In a paint brush consisting of a handle, bristles, a ferrule, binder and a plug where the plug is used to form a pocket within the bristles, the plug is formed of a resilient cellular plastic material with exposed cells on part of its surface to form a mechanical bond between the plug and the binder by means of the exposed cells.

llnited States Patent 1 lflaplan 1 3,733,638 1 May 22,1973

PAINT BRUSH CONSTRUCTION Inventor: Ronald M. Kaplan, Cedar Grove,

[73] Assignee: H & G Industries, llnc., Belleville,

Filed: May 24, 1971 Appl. No.: 146,336

US. Cl. ..15/193 Int. Cl. ..A46b 3/02, A46b 3/02 Field 0fSearch...l5/l9ll93,ll4, 104.94, 204;

References Cited UNITED STATES PATENTS 6/1950 Bixler ..l5/193 12/1964 Bolinger 4/1960 Lathrop ..15/114 X I l I I FOREIGN PATENTS OR APPLICATIONS 983,959 2/1965 Great Britain ..300/21 889,336 2/1962 Great Britain 856,868 12/1960 Great Britain 1,808,788 5/1970 Germany ..l5/104.94

Primary Examiner-Daniel Blum Attorney-Blum, Moscovitz, Friedman & Kaplan [57] ABSTRACT In a'paint brush consisting of a handle, bristles, a ferrule, binder and a plug where the plug is used to form a pocket within the bristles, the plug is formed of a resilient cellular plastic material with exposed cells on part of its surface to form a mechanical bond between the plug and the binder by means of the exposed cells.

6 Claims, 8 Drawing Figures I l I all ill PATENTEU MAY 2 2 1975 /////Hlmfl\llllllut\i\\\\\\\ I Maw INVENTOR ATTORNEYS PAINT BRUSH CONSTRUCTION BACKGROUND OF THE INVENTION It has been found advantageous to incorporate a plug within the ferrule of a paint brush. The bristles are pressed against the plug by the ferrule, and a pocket which can hold paint is formed within the brush. The plug has the further advantages that it provides a rigid surface against which the bristles can be pressed by the ferrule so that they may be held firmly in place, and it regulates the amount of bristle required.

Conventionally, plugs may be made of paper, wood, solid plastic or metal. When paper is used for the plug, it is supplied in coils which can be sued by automatic machines. Such machines can turn out up to ten thousand brushes per day. However, paper has the disadvantage that plugs of this material have a relatively short life. On the other hand, while plugs of the other materials are superior to paper plugs, they must generally be inserted by hand, so that production by an operator is limited to about 600 per day. Also, while plugs of solid plastic could also be supplied in coils suitable for use with automatic machinery, adhesion of binders and, in particular, epoxy compound to solid plastics is poor. Furthermore, solid plastic plugs are relatively heavy and costly. Moreover, in preparation of the assembly before insertion of the binder, where the plug is unyielding, it is necessary to form the assembly so tightly that the ferrule is distorted. Failing such tightness, filaments may be lost from the ferrule. Distortion of the ferrule is objectionable because unsightly and wasteful of space.

SUMMARY OF THE INVENTION Plugs of resilient cellular plastic used in the construction of paint brushes provide a strong mechanical bond with a suitable binder, provided that at least part of the surface of the plastic plug consists of exposed cells. The material, moreover, is suitable for use in automatic machinery since it can be supplied in coils and cut to size immediately prior to being inserted in the ferrule of a brush. Cells are exposed at the surface of the plug as the result of transverse slicing of the plastic strip, and as the result of removal of the edges of the strip.

Accordingly, an object of the invention is to provide a plug suitable for use in paint brushes where the plug consists of resilient cellular plastic capable of being bonded in place through exposed cells.

Another object of the invention is to provide an improved plug suitable for use in paint brushes where the plug can be inserted into the ferrule by automatic machinery.

Still another object of the invention is to provide an improved plug suitable for use in paint brushes, where the plug is durable for long periods and is low in cost.

Yet another object of the invention is to provide an improved plug suitable for use in paint brushes, where the weight of the plug is relatively low, and where the plug is resilient.

Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.

The invention accordingly comprises an article of manufacture possessing the features, properties, and the relation of elements which will be exemplified in the article hereinafter described, and the scope of the invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWING For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is an elevational view of a paint brush showing a plug therein;

FIG. 2 is a perspective view of cellular plastic strip prior to cutting as indicated by broken lines;

FIG. 3 is a perspective view of a plug cut from said strip;

FIG. 4 is a top view of a plug prior to removing the ends;

FIG. 5 is a view similar to FIG. 4 with end skins removed;

FIG. 6 is a view taken along line 6-6 of FIG. 5; FIG. 7 is a view taken along line 77 of FIG. 1; and FIG. 8 is a view taken along line 8-8 of FIG. 7.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A paint brush constructed in accordance with the present invention is indicated generally by the reference numeral 11 in FIG. I, where the brush consists of a handle 12, a ferrule 13, filaments 14, which may be of bristle or of nylon and a plug 15 indicated by the broken lines. The function of the plug is to create a pocket to hold paint, to provide a yielding surface against which the filaments may be pressed by the ferrule so that the filaments are held firmly in place, and to regulate the quantity of filament used. These functions are satisfactorily provided by a plug of resilient cellular plastic. Such a plug has the further advantage that it can be locked into the ferrule 13 by binder 16 as shown in FIGS. 7 and 8. A mechanical bond is formed between the binder and surfaces such as 17 and 18 in FIGS. 3 and 7 at which cells are exposed.

The cellular plastic is preferably suppied as coiled strip for use in automatic machines. The strip (FIG. 2) as supplied by the strip manufacturer, has a noncellular skin thereon so that no cells are exposed except, possibly, at the extreme ends thereof. A plug as shown in FIGS. 3 and 4 is obtained from the strip by cutting along the plane defined by the broken lines 19 and 20. The skin on the ends 23 is then removed from the plug by slicing along the lines 22, to yield a plug with four exposed faces (FIGS. 5 and 6).

As pointed out above, binders do not adhere adequately to the surface of solid plastic plugs. Similarly, little bonding takes place between binder and those surfaces 24 of cellular plastic from which the skin has not been removed.

In accordance with the present invention, the plug 15 having open cells exposed at two of the elongated faces 17 and at the two end faces 18, normally is positioned in the brush so that the top face is one of the elongated faces with exposed open cells (FIG. 7). When the binder is inserted into the ferrule, the binder flows into the open cells of top face 17 and the two end faces 18 and, of course, into the tip portions of the filaments 14. The principal anchoring bond to the plug is mechanical in nature and is constituted of those portions of the binder which have flowed into the end faces in a direction essentially perpendicular to the axis of the brush. The mechanical bond is reinforced by any undercuts 25 in the end faces. Some support is also supplied by the top surface 17 as a result of binder in such undercuts 26 as are present in this surface. The binder, of course, bonds strongly to the brush filaments, the ferrule and the handle, thus strongly tieing together the assembly including the plug with its exposed cells.

A preferred material for the cellular plug is foamed polyethylene; further advantages derive from using low density polyethylene as the foamed material. Such a plug is roughly half the weight of a similar polypropylene plug. The principal benefit is in a lower cost of the resultant plug where the saving may be as much as 50 percent. Polyethylene and polypropylene are within the group of compounds known as olefins which are suitable for the plug material.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above article without departing from the spirit and scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described, and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

What is claimed is:

1. In a paintbrush having a ferrule, handle and filaments inserted in said ferrule and held therein by a binder, the improvement comprising a cellular foamed, resilient, olefin plastic plug proximate the inner end of said filaments, said plug having a surface, at least part of which consists of exposed cells, said plug being mechanically bonded to said binder at said part of said surface.

2. The improvement as defined in claim 1, wherein said plug is of polyethylene.

3. The improvement as defined in claim 1, wherein said plug is of low density polyethylene.

4. The improvement as defined in claim 1, wherein said binder is an epoxy compound.

5. The improvement as defined in claim 1, wherein said plug has six faces and said cells are exposed on at least three of said faces.

6. The improvement as defined in claim 5, wherein said plug has four elongated faces and two end faces, one of said elongated faces being transverse to said ferrule and closest to said handle, said cells being exposed on said closest face and said end faces. 

1. In a paintbrush having a ferrule, handle and filaments inserted in said ferrule and held therein by a binder, the improvement comprising a cellular foamed, resilient, olefin plastic plug proximate the inner end of said filaments, said plug having a surface, at least part of which consists of exposed cells, said plug being mechanically bonded to said binder at said part of said surface.
 2. The improvement as defined in claim 1, wherein said plug is of polyethylene.
 3. The improvement as defined in claim 1, wherein said plug is of low density polyethylene.
 4. The improvement as defined in claim 1, wherein said binder is an epoxy compound.
 5. The improvement as defined in claim 1, wherein said plug has six faces and said cells are exposed on at least three of said faces.
 6. The improvement as defined in claim 5, wherein said plug has four elongated faces and two end faces, one of said elongated faces being transverse to said ferrule and closest to said handle, said cells being exposed on said closest face and said end faces. 